The objective of this research project is to investigate both the structural and the functional aspects of calcium binding and transport in skeletal and heart muscle sarcoplasmic reticulum. This project has as an additional goal the study of the relationship of calcium binding and transport to the control of muscle contraction and relaxation. BIBLIOGRAPHIC REFERENCE: Dystrophic Sarcoplasmic Reticulum Membranes. 1975. Baskin, R.J., and Hanna S.D. The Physiologist, 18, 132.